Persistence of MR3 in Chronic Myeloid Leukemia (CML) After a 2nd Stop of TKI Treatment

Inclusion Criteria: 1. CML in chronical phase (CP) under TKI treatment after failing a prior attempt to stop treatment within EURO-SKI or outside the study but according to EURO-SKI trial procedures. For the latter group this requires at least 3 years of TKI treatment (first line or second line due to intolerance to first line) before first stop, and MR4 for at least one year before stopping. 2. Treated with TKI for at least one year after having failed a prior attempt to stop TKI. Previous TKI can be any. 3. Typical BCR/ABL1 transcript (b3a2 and/or b2a2) must have been confirmed at diagnosis or later during the disease course. 4. 18 years or older. Exclusion Criteria: 1. Previous hematological relapse after first stop of TKI. 2. Previous AP/BC at any time in the history of the disease. 3. Restart of TKI without loss of MMR after first stop 4. Current participation in another clinical study. 5. Previous or planned allogeneic stem cell transplantation. 6. Patients with contra-indications to dasatinib therapy due to comorbidities. 7. Subjects with acute hepatitis B virus (HBV) infections. 8. Uncontrolled or significant cardiovascular disease. 9. Pulmonary arterial hypertension. 10. Pleural or pericardial effusions of any grade at study entry are excluded 11. History of significant bleeding disorder unrelated to CML 12. Hypersensitivity to dasatinib and excipients of dasatinib tablets.